Pontiac Repair: hard idle., fuel pressure regulator, vacuum leak

Question
ok this is my second firebird.  it has a hard start and a hard idle.  it will die if you dont hold it at 2000 rpm until it warms up then the idle regulates. it is a 1998 3.8 firebird 100k miiles.  i have checked the main vacuum line. (the one behind the maf sensor) and the pcv valve seems to be in great shape no cracks or discoloration.  my next guess was maybe the fuel pump.  but that would set a code and the engine light is off.  so that also throws the egr valve out the window.  one of my buddies told me to pull the fuel injectors.  well that is a big pain so i wanted a expert opinion first.

Answer
Hi Ryan:

Well with 100K on this it can be just about anything. I would start by checking the throttle body and plate if it's carboned up bad it will cause a lot of issues. Next the Idle control valve may be carboned up or not working propelry. You could be lacking fuel pressure yes. that engine needs about 45 PSI to run propelry. You can use carb cleaner on the engine to see if there is a vacuum leak. if there is a leak the engine speed will pick up when the cleaner is sucked in from a vacuum leak. With out the aid of a scan tool there is really not to much you can do. if you have a scan tool you need to look at the fuele trim when the car gets into closed loop and also see what the idle contol valve counts are when it's at idle. another quick check would be to pull off the vacuum hose at the fuel pressure regulator and make sure it doesn't have any raw gas in it. if it does the regulator is bad and leaking fuel into the line.
good luck :}